I sewed these but I think you could use my best friend hot glue too. I'm just not sure how that would hold up in the wash.
I made the skirts using this tutorial. (Links to my old blog Redneck Soccer Mom.)
The shirts where a LOT faster to make.
I cute a rectangle of fabric 3.5'' by 2.5'' and folded the edges under. Next, I pinned it on the shirt and sewed around the rectangle as close to the edge as possible.
I cut red rick rack, 2 shorter pieces and 3 longer pieces per shirt. I burned the ends of each piece so it wouldn't ravel. Then I sprayed them with spray adhesive. Which, if anyone knows how to get spray adhesive off a rotary cutting mat, then I would really love to know. Cause I have washed it several times and it is still sticky...still sticky a year later.
After I sprayed them I stuck them all on the shirts and then sewed a single line down each piece.